China's tech and social media giants are pouring a surge of Chinese investments into U.S. startups in order for them to attract top talent, expand their footprint, and gain edge in innovation.

An example to this is San Francisco-based SoFi (short for Social Finance Inc.), which has grown into the second-largest online lender in the market.

Joe Chen, the CEO of Chinese social networking service Renren, initially invested $4 million in helping SoFi start.

SoFi was then led to two more financings within three years, raising $230 million of investments mostly contributed by RenRen. Last month, Silver Lake, a private-equity powerhouse, invested $500 million in SoFi.

Dan Macklin, a co-founder of SoFi in San Francisco, said: "Joe is a great investor and was our investor from the early days. He saw the vision early on and pushed us to grow faster and be more aggressive."

Baidu, Alibaba and Tencent, China's giant technology companies that are dominating search, e-commerce and mobile messaging in the country, are also pouring billions into U.S.-based tech startups. They either acquire or buy stakes of fast-growing young companies that work in the hottest tech sectors such as fintech, social media, virtual reality, video games and mobile apps.

According to the data of CB Insights, a venture capital database, China's four largest Internet companies--the BAT plus e-commerce company JD.com--have invested $5.6 billion in 48 U.S. tech deals over the past two years.

Alibaba invested $793 million in a virtual reality startup Magic Leap, $250 million in ride-sharing app Lyft, $215 million in mobile messaging app Tango, $205 million in subscription service ShopRunner, and $200 million in social media company Snap.

It also invested $120 million in mobile gaming startup Kabam, $50 million in remote-control app Peel, and $50 million in the app search engine Quixey.

Tencent, on the other hand, invested $400 million in game developer Epic Games and another $400 million in Riot Games.

Baidu is not outdone as it invested $30 million in mobile safety firm TrustGo and $10 million in mapping company Indoor Atlas.